1. Technical Field
This invention relates to a non-destructive method for the early detection of organic materials deposited on the internal surface of a conduit through which fluid flows in a continuous or semi-continuous manner. This invention also relates to a method of removing at least a portion of the organic deposit. The present methods are useful for the early detection of the formation and the removal of undesirable deposits of organic, biological or biochemical materials on the internal surfaces of reactors and pipelines subjected to continuous or semi-continuous flows. Examples of these are industrial plant reactors, water pipelines, oil pipelines, power plant condensers and the like.
2. Background Art
Biofilms are organic slime layers consisting of microbial and higher life forms held together by an inorganic and/or organic matrix. However, biofilms may contain other chemical compounds and particulate materials in addition thereto. Biofilms form in aqueous environments by deposition of biological and other materials on the internal surfaces of containers, conduits and the like.
In many instances, biofilms can have a positive influence on the overlaying water quality, particularly in terms of suspended and dissolved materials contained therein. For this reason, biofilms may be an asset in both natural systems such as streams and lakes, and in engineering systems such as fixed-film biological waste water treatment plants and the like.
On the other hand, in most engineered systems biofilms are considered a nuisance which results at times in energy losses (in fluid flow systems), reduction of cooling capacity (heat-exchangers), enhancement of corrosion potential (oil pipelines), danger to public health (drinking water supplies) and the like. Therefore, the formation of biofilms must be closely monitored in order to prevent the occurrence of extreme conditions. Biofilm monitors now in use in general measure one of the above negative effects and signal when some preset value is reached. However, since the variable which is monitored is some undesirable effect, in order to become detectable, the value of such variable may already be in the undesirable range.
Accordingly, there is still a need for early monitoring and control of biofilms and methods of detecting their formation and the removal of at least a portion of the biofilm in an as early as possible stage, particularly before levels of undesirable effects are reached.